To date it has arrived at this, by which time I had decided to soften the blue of the sky, use the same hue for irises in the foreground and reduce the width area of the left and right flower borders.
Working backwards, here are some images showing the transitions as I worked without any particular ref in mind, apart from the shapes of the tall hollyhocks on the left.
Here you can see the earlier darker more vibrant sky I obliterated and the wider borders I removed.
I think this was the first photo I took, simply to remind myself how I had begun.
Where it now takes me I have no idea after the best part of a week away, but it certainly contrasts well with the original painting I wish to pair it with shown below, which you may remember from a much earlier posting.